package com.atguigu.cart.interceptor;

import com.atguigu.cart.vo.UserInfoTo;
import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberRespVO;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * @author bobo
 * @date 2023/7/28
 * @apiNote
 * 在执行目标方法之前，判断用户的登陆状态。并封装传递给Controller目标请求
 */

public class CartInterceptor implements HandlerInterceptor {

    public static final ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    /**
     * 前处理
     *  目标方法执行之前
     * @param request  请求
     * @param response 响应
     * @param handler  处理程序
     * @return boolean
     * @throws Exception 异常
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();

        HttpSession session = request.getSession();
        MemberRespVO member = (MemberRespVO) session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member != null){
            //用户登陆了
            userInfoTo.setUserId(member.getId());
        }
        Cookie[] cookies = request.getCookies();
        if (cookies != null && cookies.length > 0){
            for (Cookie cookie : cookies) {
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)){
                    userInfoTo.setUserKey(cookie.getValue());
                    userInfoTo.setTempUser(true);
                }
            }
        }
        //如果没有临时用户，一定分配一个临时用户
        if (StringUtils.isEmpty(userInfoTo.getUserKey())){
            String s = UUID.randomUUID().toString();
            userInfoTo.setUserKey(s);

        }

        //目标（COntroller）方法执行之前
        threadLocal.set(userInfoTo);

        return true;
    }

    /**
     * 处理后
     * 分配临时用户，让浏览器储存
     * @param request      请求
     * @param response     响应
     * @param handler      处理程序
     * @param modelAndView 模型和视图
     * @throws Exception 异常
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

        UserInfoTo userInfoTo = threadLocal.get();
        //如果没有临时用户，一定保存一个临时用户
        if (userInfoTo.isTempUser()){
            //持续的延长cookie过期时间
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
            cookie.setDomain("gulimall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }

    }
}
